Many think they know. Below is a general idea of the amount of alcohol in standard drink sizes.
Examples of a standard drink:
12 oz beer (3-5% alcohol by volume/ABV)
4-5 oz wine or champagne (9-16% ABV)
1.5 oz 80 proof liquor (40% ABV)
1 oz 100 proof liquor (50% ABV)
.5 oz Bacardi™ 151 (75.5% ABV)
1 Tbsp Everclear™/grain alcohol (95% ABV)